During the last decade, the telecommunication industry has produced an explosion of wireless technology. This growth, together with recent developments in hardware miniaturization, has opened a new dimension to future wireless networks whose ultimate goal is to provide universal personal communications. To achieve such an objective, the next generation personal communications networks will need to be able to support a very high level of user traffic along with a wide range of high-quality services with varying bit rates. These future services are likely to include video and LAN applications which require high speed transmission rates of several Mbps. However, the ability to achieve high bit rates at low error rates over wireless channels is severely restricted by the propagation characteristics of the wireless environment where signals typically arrive at the receiver via a scattering mechanism resulting in multiple propagation paths with different time delays, attenuation, and phasors. This causes a spread in delay times which imposes a limit on the maximum transmission rate. These restrictions manifest themselves as intersymbol interference (ISI) which leads to the introduction of an irreducible error floor. Therefore, without countermeasures to mitigate the delay spread impairments the information rate is usually limited to be under 1 Mbps when user mobility prevents steady line-of-sight conditions.